[U-Boot] [PATCH 8/9] Tegra30: Add common pinmux config in board_early_init_f

Stephen Warren
2012-09-18T21:53:15Z

On 09/18/2012 03:32 PM, Tom Warren wrote:
...
> As far as I'm aware, an FDT pinmux for Tegra (which is on my plate,
> but quite a bit behind T30) would be essentially the same deal - one
> large list of mux settings per build/board.

Initializing pinmux from DT can work either way, depending on how the DT
author wrote the DT file.

The pinmux DT node can contain a pinmux configuration which is applied
as soon as the pinmux driver loads. This configuration can contain as
little as you want (even nothing) all the way through to containing the
entire board's static pinmux configuration.

For portions of the pinmux settings which the pinmux driver's own DT
node doesn't configure (if any, based on the above), the relevant
individual driver DT node can configure the pinmux as required, and that
configuration would be applied when the relevant driver loads and parses
its DT node.

In practice, so far, all the kernel board files for Tegra almost
exclusively use static muxing in the pinmux controller's own DT node.
However, there are a couple small dynamic cases (e.g.
Seaboard/Springbank's pinctrl-based I2C mux for example).